The present invention relates to a pneumatic stowing apparatus especially for filling up dams in an underground mine gallery by blowing mine waste, resulting from blasting operations during advance of the mine gallery, by means of compressed air to a point of use.
It is known for years to transport comminuted mine wastes up to an upper grain size of about 80 mm by compressed air to fill mine galleries from which coal has been removed, to avoid collapse of such mine galleries. Usually machines with rotating cell wheels or a plurality of chambers are used for flinging the mine waste into a chamber of the machine from which the mine waste is subsequently transported by a continuous air stream through a transport conduit to the point of use.
The pneumatic stowing apparatus so far known permit however only transport of relatively small size particles since the individual particles are taken along by the passing air stream and are held during the transport in floating condition.
However, in mining operations there occurs quite often the necessity to transport rough non-comminuted mine waste. This necessity arises usually when the transporting distances are not too long. Such a necessity arises for instance during filling up dams extending along the mine gallery with rough and non-comminuted mine waste, resulting from blasting operations during advance of the mine gallery. Such filling up or stowing of mine waste may be carried out by hand and in some cases a so-called annular chamber jet blower is used. The disadvantage of such a blower consists of its high consumption of compressed air, its very low range of transmission, as well as its high wear.
In addition, backfilling scrapers and band catapults are also used for backfilling of rough mine waste. These known apparatus have however been found unsuitable, due to the great noise connected therewith, their short range of transmission and their exceedingly large wear.